In radiotelephone systems such as the Global System for Mobile Communications (GSM) radiotelephone system in use in Europe, a SIM card is inserted into a radiotelephone for providing subscriber identification, billing information and other information concerning the operation of the radiotelephone. The SIM is a key component of the GSM and typically comprises a card which is inserted into a GSM phone in order to make the phone work.
In a typical cellular telephone communication system, each subscriber unit is assigned a mobile subscriber identification (MSI) which uniquely identifies the subscriber unit from other subscriber units. In the European cellular communication system, one such identifier is the international mobile subscriber identification number (IMSI).
It is highly desirable to provide a personal communication system which utilizes a personal telecommunications device or subscriber unit which is operable in various available telecommunications systems across all available cellular frequencies and which is operable with satellite based communication systems such as the Iridium based communications system from Motorola Inc.
In the present telecommunications environment, SIM cards are used to allow the SIM card holder to have access to any telecommunications device such as a cellular telephone which will receive the SIM card. The SIM card is used primarily to provide a customer profile from which the customer may be billed for usage of the telecommunications network. Thus, the SIM card is used to authenticate or authorize a user.
With the advent of subscriber units which are useable in satellite systems and across other systems as well, it is desirable to provide for limited use of subscriber units. In certain circumstances it is desirable to allow a subscriber unit to be used only by a single user. In other instances it is desirable that a single user decides additional specific users who are permitted to use the subscriber unit. By providing these security features, the incidence of theft or misappropriation of subscriber units may be decreased.